Induction-motor.



J. B. WIARD.

INDUCTION MOTOR.

APPLICATION FILED FEB. 20, 1906.

91 7,224. Patented Apr. 6, 1909.

Fig. 2.

Fig. 1.

WiCnesses: lnvencfor:

W (if/4%,

I John .Winrd.

. I b l W M i bq UNITED STATES PATENT oFFIoE.

-. Jens B. or Linux, mssaonusnrrs, ASSIGNOB .ro arsenal. ELEOTRIGI-WBPORATION OF NEW YORK.

INDUCTION-m Mariam. s oaasaum of Letters Patent. Patented Lprllb, isoo.Appllcatlen filed Iebruary 80, 190 6. Serial No. To all whom it mumrotor shaft is hollowed out to receive the rod Be a known that 'I,Jess's. wmm, a citizen of the United States, residing at Lynn,

- county of Essex, and State of Massachusetts,

have invented certain new and useful Improvements in Induction-Motors,of which the following is a s cification.

My invention re ates to induction motors of the type in which the rotoris rovided with switch contacts for controlling the efiective resistanceof the rotor winding, and

, its object is to provide a novel arrangement of the rotor and contactswhereby an economy of space is secured and the contacts are protectedfrom dust and corrosion. I

My invention broadly consists in inclosin the switch contacts within thelaminated body of the rotor. With this arrangement not only is the spaceusually occupied by these contacts saved but also the rotor body itselfserves to protect the contacts from dust and other sources of injury ordeteriora- 'tion.

' In the drawing, A represents the stator orprimary member which isconstructed in the usual manner and carries the usual primary winding a.I

B represents the rotor body carrying the rotor windin which, in thepresent case,

is shown as ormed of two portions,one a high-resistance short-circuitedwinding 6 of.

, the squirrel-cage type, and the other a low resistance olgen-circuitedcoil winding 0. The termina of the low-resistance C are connected tocontacts 0 which exten from one end of the rotor body intoaxiallyextending tunnels therein.

D represents an axiall -movable s ider,

. carried at the opposite on of the rotor ody,

and supporting contacts (I, which extendinto the tunnels in the rotorbody, and, when, the spider is moved axially, e age thecontacts *0 so asto short-circuit t e. low-resistance rotor winding. The spider D is oerated b means of an axially-movable rod towhic it 'is connected bymeans of a pin a. The

E and is slotted to allow for the axial movement of the in e. The outerand of the rod E. is provi ed with a relatively rotatable handle F, bymeans of which the rod may be pushed inward toshift thespider and bringthe contact d into e agement with the con tact c. The spider ispreferably provided with the usual spring-actuated latch 9 shown in Fig.2, which releasably holds the spider in its two extreme positions.

The operation of the device clearly appears from'the above description.At starting the spider D is in the position shown, and only t ehigh-resistance squirrel cage winding b is effective. The motorconsequently starts with high torque due to the high-resistance of thesecondary circuit. When the motor is ulp to speed the handle'F is pushedinward, t ereby shifting the spider D toward the rotor core and bringingthe contacts (1 into engagement with the contacts 0. The lowresistanceportion of the rotor winding is thereby short-circuited and the motoroperates with a low-resistance secondary circuit.

Although I have shown the rotor provided with a winding of two separateortions of high and low resistance respective y, it will be understoodthat my invention in its broader aspect is not limited to such anarrangement, but may be used to advantage in a motor having an desiredarrangement and connections o the rotor windin What I claim as new andesire to secure by Letters Patent of the United States, is,

1. In an induction motor, a laminated rotor body provided withtunnels, awinding carried thereby, and switch contacts inclosed within thetunnels, and connected in the circuit o'f said winding.

2. In an induction motor, a laminated ro-' torjbody provided withtunnels, a winding carried thereby, switch contacts inclosed within thetunnels and connected with said -winding, and relatively-movablecontacts adapte tacts.

3. In an induction motor, a laminated rotor body provided with tunnels,a winding 0 engage the first-mentioned concarried thereby, switchcontacts inclosed within the tunnels connected in circuit with said.winding, relativel -movable contacts adapted to engage the t-mentionedcontacts, and connections whereby said relatively-lnovable contacts nayibe lcontrolled w e lyv h e. the 0129 r nn a, a

4. In an induction motor, a rotor windmg,

a laminated rotor body supporting said winding and provided with'tnnnels extending axially through the laminatlons, contacts extendingintosaid tunnelsfrom one-end of the rotor and connected to said winding,and axiall -movable contacts extending into said tunnels from theopposite end of therotor.

' 5. In an induction motor, a rotor winding,

a laminated rotor body supporting said win ing and provided with tunnelsextending ax1ally through the lamin'ations, contacts extending into saidtunnels from one end of the rotor'i'and connected to said winding,axiallymovable contacts extending into said tunnels from theopposite-end of the rotor, and

.- connections whereby said axially-movable ot er end of the rotor, andcontacts carried by said spider extending into said tunnels. I

7. In an induction motor, a rotor winding, a laminated rotor bodysupporting said winding and provided with tunnels extending axially trough the laminations, contacts extending into said tunnels from one endof the rotor and'connected to said windin an axially-movable spidercarried at the ot or end of the rotor, contacts carried by said spiderextending into said tunnels, and connections whereb said spider may bemoved manually Whll the motor is running. 8. In an-induction motor, alaminated ro tor body provided with tunnels, a high-resistanceshort-circuited winding and a low-resistance opencircuited windingcarried thereby, and switch contacts inclosed within the tunnelsarrangedand connected to shortcircuit said low-resistance winding.

9, Inan induction motor, a laminated rotor body lprovided with tunnels,a high-resistance' s ort-circuited winding and a lowresistanceopen-circu'ited winding carried thereby, switch contacts inclosed withinthe tunnels connected to said low-resistance winding, andrelatively-movable short-circuiting contacts adapted to engage the firstnamed contacts.

-10.'-In an induction motor, a high-resistance short-circuited winding,a low-resistance opeh-circuited winding, a laminated rotor bodysupporting said windings and provided with tunnels extending axiaflythrough the laininations, contacts extending into said tunnels from oneend of the rotor and con- .nected to said low-resistance winding, and

axially-movable short-Circuiting contacts ex,- tending into said tunnelsfrom the opposite end of the rotor.

11. In an induction motor, a high-resistance short-circuited winding, alow-resistance open-circuited winding, a laminated rotor bod supportingsaid windings and provided with tunnels extending axially through thelaminations, contacts extending into said tunnels from one end of therotor and connected to said low-resistance winding, an axially-movablespider carried at the other end of the rotor, and short-'circuitingcontacts carried by said spider and extending into said tunne s.

In Witness whereof, I have hereunto set my hand this seventeenth day ofFebruary,

JOHN B. WI-ARI).

, W'itnesses:

' JOHN A. MCMANUS, Jr., HENRY O. WESTENDARP.

